Flange fitting for tubular structures

ABSTRACT

Devices, systems, and methods are directed to automated techniques for fitting flanges to tubular sections used to form tubular structures, such as large-scale structures used in industrial applications (e.g., wind towers and pipelines). As compared to manual techniques for fitting flanges to tubular sections, the devices, systems, and methods of the present disclosure facilitate faster attachment of flanges, which may be useful for achieving cost-effective throughput. By way of further comparison to manual techniques, the devices, systems, and methods of the present disclosure may, further or instead, facilitate achieving tighter dimensional tolerances. In turn, such tighter dimensional tolerances may be useful for forming thinner-walled, lighter, and lower cost tubular structures. Still further or in the alternative, automated techniques for fitting flanges to tubular sections may facilitate attachment of multipiece flanges or other non-traditional flange geometries.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional PatentApplication No. 62/696,717, filed on Jul. 11, 2018, the entire contentsof which are incorporated herein by reference.

GOVERNMENT LICENSE RIGHTS

This invention was made with government support under USDA SBIR Phase IIAward 2016-33610-25675, awarded by the United States Department ofAgriculture/National Institute of Food and Agriculture. The UnitedStates government has certain rights in this invention.

BACKGROUND

Many large-scale tubular structures useful for various industrialapplications are formed by connecting tubular sections to one another orto a foundation using one or more flanged connections. Each flangedconnection is typically formed by attaching a flange to a respectivetubular section. The process of attaching a flange to a tubular section,however, is often difficult and lengthy, particularly in instancesrequiring non-standard geometries such as multi-piece flanges. Thus,attaching a flange to a tubular section can be a rate-limiting step inthe production of a tubular structure, requiring extra equipment andlabor to achieve suitable production throughput.

Applications requiring high-precision fit-up can be particularlychallenging with respect to attaching a flange to a tubular section usedin the formation of a tubular structure. In particular, whilehigh-precision fit-up can increase the fatigue strength of astructure-flange joint and may facilitate using less material in atubular structure (thus reducing cost), the cost associated with addedtime required to achieve high precision fit-up often outweighs thestructural savings realized through high-precision fit-up.

Accordingly, there remains a need for efficiently fitting flanges totubular sections used to form tubular structures for various large-scaleapplications.

SUMMARY

Devices, systems, and methods are directed to automated techniques forfitting flanges to tubular sections used to form tubular structures,such as large-scale structures used in industrial applications (e.g.,wind towers and pipelines). As compared to manual techniques for fittingflanges to tubular sections, the devices, systems, and methods of thepresent disclosure facilitate faster attachment of flanges, which may beuseful for achieving cost-effective throughput. By way of furthercomparison to manual techniques, the devices, systems, and methods ofthe present disclosure may, further or instead, facilitate achievingtighter dimensional tolerances. In turn, such tighter dimensionaltolerances may be useful for forming thinner-walled, lighter, and lowercost tubular structures. Still further or in the alternative, automatedtechniques for fitting flanges to tubular sections may facilitateattachment of multipiece flanges or other non-traditional flangegeometries.

According to one aspect, a system may include a plurality of tuberollers upon which a tubular section is supportable as the tubularsection rotates in a rotation direction, a fitting unit including alocating roller and a pusher roller spaced relative to one another todefine therebetween a pinch through which a flange is rotatable in therotation direction, a sensing unit including one or more sensorspositioned relative to the pinch to detect a radial offset of the flangeand the tubular section moving in the rotation direction, and acontroller in communication with the sensing unit and the fitting unit,the controller configured to receive one or more signals indicative ofthe radial offset, to compare the one or more signals indicative of theradial offset to a target value, and, based at least in part on thecomparison, to move the locating roller to adjust the radial offsetbetween the flange and the tubular section moving in the rotationdirection.

In certain implementations, the plurality of the tube rollers mayinclude a first set of the tube rollers and a second set of the tuberollers. The first set of the tube rollers and the second set of thetube rollers may be apart from one another along a circumference of thetubular section as the tubular section moves along a path of movement inthe rotation direction. Further, or instead, the first set of the tuberollers and the second set of the tube rollers may be actuatable to moverelative to one another. Still further, or instead, the first set of thetube rollers and the second set of the tube rollers may be actuatable tomove relative to one another as the tubular section moves in therotation direction. In some instances, the one or more sensors may bepositioned to detect the radial offset of the flange and the tubularsection between the first set of the tube rollers and the second set ofthe tube rollers along the path of movement of the tubular section inthe rotation direction.

In some implementations, the pinch defined by the locating roller andthe pusher roller may be between at least two of the tube rollers of theplurality of the tube rollers along a path of movement of the tubularsection in the rotation direction.

In certain implementations, at least one of the tube rollers of theplurality of the tube rollers may be passive.

In some implementations, the fitting unit may include a first actuatormechanically coupled to the locating roller and the pusher rollerdefining the pinch. Further, or instead, the controller may beconfigured to actuate the first actuator to move the pinch to adjust theradial offset between the flange and the tubular section moving in therotation direction.

In certain implementations, the locating roller may define a channelengageable with the flange to restrict axial movement of the flange asthe flange rotates through the pinch in the rotation direction.

In some implementations, the fitting unit may include a second actuatormechanically coupled to the locating roller. Further, or instead, thesecond actuator may be actuatable to change an axial gap between theflange and the tubular section moving in the rotation direction.Additionally, or alternatively, at least one of the locating roller andthe pusher roller may be passive with respect to movement of the flangein the rotation direction.

In certain implementations, the system may include a joining unitpositioned relative to the pinch to join a point of the flange to thetubular section following movement of the point of the flange throughthe pinch in the rotation direction. In some instances, the one or moresensors may be positioned relative to the joining unit to measure theradial offset at the point of the flange following movement of the pointof the flange past the joining unit. Further or instead, the sensingunit may be fixed relative to the joining unit such that the one or moresensors measure the radial offset at a fixed location relative to thejoining unit. Additionally, or alternatively, the sensor may furtherinclude a cooler including a fluid inlet, a fluid outlet, and a coolingchamber in fluid communication with the fluid inlet and the fluidoutlet, the sensing unit defining a volume in which at least a portionof each of the one or more sensors is disposed, and the volume inthermal communication with the cooling chamber of the cooler. Further,or instead, the joining unit may include a weld head.

In some implementations, each of the one or more sensors may bepositionable in contact with one or more of the flange or the tubularsection moving in the rotation direction.

In certain implementations, the locating roller may be movable in anaxial direction relative to the tubular section engaged by the pluralityof tube rollers. Additionally, or alternatively, the system may includea gap sensor arranged to measure an axial gap between the flange and thetubular section moving in the rotation direction. As an example, thecontroller may be configured to receive a signal indicative of the axialgap between the flange and the tubular section moving in the rotationdirection, to compare the axial gap to a target gap, and, based on thecomparison of the axial gap to the target gap, to move the locatingroller in the axial direction relative to the tubular section engaged bythe plurality of tube rollers. The signal indicative of the axial gapbetween the flange and the tubular section may, for example, include auser input.

In some implementations, the one or more signals indicative of theradial offset may include a user input.

According to another aspect, a method of fitting a flange to a tubularsection may include rotating the tubular section, supported on aplurality of tube rollers, in a direction toward a joining unit,rotating at least one portion of the flange in the direction toward thejoining unit, receiving one or more signals indicative of a radialoffset between the tubular section and the at least one portion of theflange, comparing the one or more signals indicative of the radialoffset to a target value, and based at least in part on the comparisonof the one or more signals to the target value, adjusting the radialoffset between the at least one portion of the flange and the tubularsection as the tubular section and the at least one portion of theflange each rotate in the direction toward the joining unit.

In certain implementations, rotation of the tubular section and the atleast one portion of the flange in the direction toward the joining unitmay be about an axis perpendicular to a direction of gravity.

In some implementations, in a radial direction, the at least one portionof the flange may be more rigid than the tubular section.

In certain implementations, each tube roller in the plurality of thetube rollers may be spaced apart from one another circumferentiallyalong an outer surface of the tubular section. Further or instead,rotating the tubular section includes driving at least one roller incontact with the outer surface of the tubular section.

In some implementations, rotating the at least one portion of the flangein the direction toward the joining unit may include engaging firstsurface of the at least one portion of the flange with a pusher roller,and engaging a second surface of the at least one portion of the flangewith a locating roller such that the at least one portion of the flangeis pinched between the locating roller and the pusher roller.

In certain implementations, the one or more signals indicative of theradial offset may be received from one or more sensors as the tubularsection and the at least one portion of the flange move in the directiontoward the joining unit.

In some implementations, the one or more signals indicative of theradial offset include one or more of the following: a radius ofcurvature of the tubular section between two of the tube rollers of theplurality of the tube rollers; a stress level in the tubular section; adistance between two points along a circumference of the tubularsection; a radial distance between a location on the tubular section anda corresponding circumferential location on the flange; or a distancebetween a point on the tubular section and a fixed point external to thetubular section. Additionally, or alternatively, the one or more signalsindicative of the radial offset include one or more of the following:torque required to actuate at least one of tube roller of the pluralityof the tube rollers; rotational speed of at least one of the tuberollers of the plurality of the tube rollers; or a position of at leastone of the tube rollers of the plurality of the tube rollers.

In certain implementations, the one or more signals indicative of theradial offset may include a user input.

In some implementations, the at least one portion of the flange may be aunitary hoop. Further, or instead, the target value of the radial offsetmay be based on a first circumference of the unitary hoop relative to asecond circumference of the tubular section.

In certain implementations, the target value may vary as the at leastone portion of the flange and the tubular section rotate in thedirection toward the joining unit. Further, or instead, adjusting theradial offset may include receiving an indication of circumferentialspacing between a first tick mark on the tubular section and a secondtick mark on the at least one portion of the flange, and adjusting thetarget value for the radial offset based on the indication ofcircumferential spacing of the first tick mark relative to the secondtick mark.

In some implementations, adjusting the radial offset may include movingat least one of the tube rollers of the plurality of the tube rollers ina direction having a radial component relative to the tubular section asthe tubular section and the at least one portion of the flange rotate inthe direction toward the joining unit. As an example, adjusting theradial offset may include pushing the at least one portion of the flangein a direction having a radial component relative to the at least oneportion of the flange as the at least one of the tube rollers of theplurality of the tube rollers moves in the direction having a radialcomponent relative to the tubular section.

In certain implementations, adjusting the radial offset may includepushing the at least one portion of the flange in a direction having aradial component relative to the at least one portion of the flange asthe plurality of the tube rollers remain in a fixed radial position andin a fixed axial position as the at least one portion of the flange andthe tubular section each rotate in the direction toward the joiningunit. Additionally, or alternatively, the method may include adjustingone or more of the fixed radial position or the fixed axial position ofat least one tube roller of the plurality of the tube rollers as thetubular section is stationary.

In some implementations, the method may further or instead includeadjusting an axial gap between the tubular section and the at least oneportion of the flange. For example, adjusting the axial gap between thetubular section and the at least one portion of the flange may includemoving the at least one portion of the flange in an axial direction asthe tubular section remains fixed in the axial direction.

In certain implementations, the method may further or instead includejoining the at least one portion of the flange to the tubular section asthe tubular section and the at least one portion of the flange rotate inthe direction toward the joining unit.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a perspective view of a fit-up system including a plurality oftube rollers, sensing unit, a fitting unit, a joining unit, and acontroller, the fit-up system shown forming a tubular assembly.

FIG. 2A is a schematic representation of the tubular assembly of FIG. 1,the tubular assembly including a flange mechanically coupled to atubular section.

FIG. 2B is a cross-sectional side view along line 2B-2B in FIG. 2A, thecross-sectional side view representing a portion of the flange mated inradial alignment to the tubular section in the tubular assembly.

FIG. 2C is a cross-sectional side view along line 2C-2C in FIG. 2A, thecross-sectional side view representing a portion of the flange matedwith a radial offset to the tubular section in the tubular assembly.

FIG. 3A is a side view of the tubular section of FIG. 2A supported onthe plurality of tube rollers of the fit-up system of FIG. 1.

FIG. 3B is a side view of a roller assembly including a pair of the tuberollers of the plurality of the tube rollers of the fit-up system ofFIG. 1.

FIG. 4A is a perspective view of the fitting unit of the fit-up systemof FIG. 1.

FIG. 4B is a schematic side view of a locating roller of the fittingunit of FIG. 4A engaged with a radial section of the flange of FIG. 2A.

FIG. 5A is a side view of the sensing unit and the joining unit of thefit-up system of FIG. 1.

FIG. 5B is a partial cross-sectional view of a sensor of the sensingunit of the fit-up system of FIG. 1.

FIG. 5C is a partially exploded view of the partial cross-section of thesensor shown in FIG. 5B.

FIG. 6 is a flowchart of an exemplary method of fitting a flange to atubular section to form a tubular assembly.

FIG. 7 is a schematic representation of a top view of a system detectingtick marks on a flange and on a tubular section to determine a targetvalue for a radial offset of the flange and the tubular section.

FIG. 8 is a schematic representation of a cross-sectional side view of aflange axially spaced from a tubular section by an axial gap.

FIG. 9 is a schematic representation of a tubular assembly including aT-shaped flange mechanically coupled to a tubular section.

FIG. 10A is a perspective view of a fit-up system including a hold-downunit.

FIG. 10B is a side view of the hold-down unit of the fit-up system ofFIG. 10A.

Like reference symbols in the various drawings indicate like elements.

DETAILED DESCRIPTION

The embodiments will now be described more fully hereinafter withreference to the accompanying figures, in which exemplary embodimentsare shown. The foregoing may, however, be embodied in many differentforms and should not be construed as limited to the exemplaryembodiments set forth herein.

All documents mentioned herein are hereby incorporated by reference intheir entirety. References to items in the singular should be understoodto include items in the plural, and vice versa, unless explicitly statedotherwise or clear from the text. Grammatical conjunctions are intendedto express any and all disjunctive and conjunctive combinations ofconjoined clauses, sentences, words, and the like, unless otherwisestated or clear from the context. Thus, the term “or” should generallybe understood to mean “and/or,” and the term “and” should generally beunderstood to mean “and/or,”

Recitation of ranges of values herein are not intended to be limiting,referring instead individually to any and all values falling within therange, unless otherwise indicated herein, and each separate value withinsuch a range is incorporated into the specification as if it wereindividually recited herein. The words “about,” “approximately,” or thelike, when accompanying a numerical value, are to be construed asincluding any deviation as would be appreciated by one of ordinary skillin the art to operate satisfactorily for an intended purpose. Ranges ofvalues and/or numeric values are provided herein as examples only, anddo not constitute a limitation on the scope of the describedembodiments. The use of any and all examples or exemplary language(“e.g.,” “such as,” or the like) is intended merely to better illuminatethe embodiments and does not pose a limitation on the scope of thoseembodiments. No language in the specification should be construed asindicating any unclaimed element as essential to the practice of thedisclosed embodiments.

In the disclosure that follows, the terms “horizontal” and “vertical”refer to directions in a coordinate system defined by an installedsystem supported on a substantially flat surface (e.g., on a factoryfloor or at an installation site). That is, a horizontal orientationshall be understood to be substantially parallel to the substantiallyflat surface supporting the installed system. A vertical orientationshall be understood to be perpendicular to the horizontal orientationand generally parallel to a direction of gravity.

In general, as used herein, a “tubular section” may be a hollow andsubstantially cylindrical (e.g., having a substantially constantdiameter to within a dimensional tolerance of the tubular structure orhaving a tapering diameter along a length of the cylinder) such thateach tubular section defines a cylindrical coordinate system. Thus, asused herein, the terms “axial” and “radial” shall be understood to beused in a manner consistent with use of those terms with respect to acylindrical coordinate system. For example, axial shall be understood torefer to a direction parallel to a center axis defined by the tubularsection and extending along the length of the tubular section, and theterm radial shall be understood to refer to a radial dimension in adirection perpendicular to the center axis defined by the tubularsection. Accordingly, as described in greater detail below, an axial gaprefers herein to a space between an edge of a tubular section and anedge of a flange in the axial direction, with an axial gap of zerocorresponding to an abutting relationship between the edge of thetubular section and the edge of the flange. As also described in greaterdetail below, a radial offset shall refer to a shift in radial positionof the flange and the center axis of the tubular section relative to oneanother, with a zero radial offset corresponding to alignment of theinner diameter of the flange to the inner diameter of the tubularsection. Further, in the context of the tubular section and the flange,a rotation direction shall be understood to be a direction of rotation(e.g., clockwise or counterclockwise) of the circumference of thetubular section about the center axis defined by the tubular section.

As used herein, unless otherwise specified or made clear from thecontext, the term “flange” refers generally to any of various differenttypes of structures (e.g., a rim or a collar) positionable along atleast a portion of a circumference of the tubular section. In general,such a flange may facilitate connecting the tubular section with afoundation or another tubular section and/or to strengthen the tubularsection. As an example, a flange may include a radial section projectingradially inward and/or radially outward with respect to an outer surfaceof the tubular section, and this radial projection of the flange may beuseful for connecting to a foundation or another tubular section withoutcompromising strength of the tubular section. In certainimplementations, as described in greater detail below, the flange may beformed using a plurality of sections that are coupled to one another aseach section is coupled to the tubular section. The plurality ofsections may collectively circumscribe the circumference of the tubesection. In other implementations, as also described in greater detailbelow, the flange may be a unitary hoop having nominally (e.g., towithin dimensional tolerance of the tubular structure being formed) thesame diameter as the diameter of the tubular section.

As used herein, the term “tubular assembly” shall be understood to referto an assembly including at least a section of a flange mechanicallycoupled to a tubular section. Each tubular assembly should be generallyunderstood to be at least a portion of a larger tubular structure. Thus,in some instances, the tubular assembly may correspond to an entiretubular structure. In other instances, the tubular assembly may be aportion of a larger tubular structure. For example, at least one end ofthe tubular assembly may include a flange to facilitate connecting thetubular assembly to a foundation and/or to one or more other tubularassemblies of a tubular structure.

Further, unless otherwise specified or made clear from the context, thetubular assemblies described herein may be used to form at least aportion of any one or more different types of tubular structures usefulfor supporting loads in a variety of industrial applications. Examplesof such tubular structures may include, but are not limited to, towersfor supporting mechanical equipment (e.g., wind turbines) or pipes fortransporting material.

Referring now to FIGS. 1, 2A, 2B, and 2C, a fit-up system 100 may beoperated to form a tube assembly 200 including a tubular section 202 anda flange 204. The flange 204 may be generally “L” shaped, having aradial section 205 extending radially inward such that the flange 204may be connectable to a foundation or another tubular assembly along aninner volume of a tubular structure. Such an orientation of the flange204 may be useful, for example, in the context of towers used to supportwind turbine machinery, with the radially inward extent of the flange204 serving to support auxiliary equipment (e.g., ladders, cables, etc.)that may be accessed within an inner volume of a tubular structureduring inclement weather. Further, or instead, the inward extension ofthe radial section 205 may facilitate inspecting bolt connections of thetubular structure without needing to climb the outside of the tubularstructure.

Although the tubular section 202 may have a generally roundcircumferential shape at any point in the axial direction, the tubularsection 202 may sag in the radial direction due to gravitationaleffects. This type of sagging may be particularly pronounced, forexample, in instances in which the tubular section 202 has a large innerdiameter relative to a wall thickness of the tubular section 202. Insuch instances, the tubular section 202 may have a poor overall shapematch with the flange 204, which may be stiffer than the tubular section202. That is, at the same nominal inner diameter, the flange 204 maygenerally maintain a rounder shape as compared to the tubular section202. Such differences in shape between the tubular section 202 and theflange 204 present challenges with respect to adequately aligning thetubular section 202 and the flange 204 along a circumference of thetubular section 202 to form the tube assembly 200 according topredetermined dimensional tolerances (e.g., tolerances associated withlarge-scale industrial applications).

To facilitate addressing the aforementioned challenges associated withaligning shapes of the tubular section 202 and the flange 204 to formthe tube assembly 200, the fit-up system 100 may include a plurality oftube rollers 102, a fitting unit 104, a sensing unit 106, and acontroller 108. The tube rollers 102 may support the tubular section 202and rotate the tubular section 202 in a rotation direction 109. Further,or instead, the controller 108 may be in electrical communication withat least the fitting unit 104 and the sensing unit 106 to controlalignment of a first inner surface 206 of the tubular section 202 and asecond inner surface 208 of the flange 204, with a difference in radialalignment of the first inner surface 206 and the second inner surface208 referred to here as a radial offset 210. In general, it should beappreciated that the radial offset 210 may be controlled along variousdifferent points (e.g., at discrete points or continuously) along thecircumference of the tubular section 202. Additionally, oralternatively, the radial offset 210 at different points along thecircumference of the tubular section 202 may have any of variousdifferent values suitable for achieving overall alignment of the tubularsection 202 and the flange 204. For the sake of illustration, however,two examples are shown: an example in which the radial offset 210 iszero (also referred to herein as radial alignment) such that the firstinner surface 206 of the tubular section 202 and the second innersurface 208 of the flange 204 are aligned as shown in FIG. 2B; and anexample in which the radial offset 210 is nonzero such that the firstinner surface 206 of the tubular section 202 and the second innersurface 208 of the flange 204 are offset as shown in FIG. 2C.

In use, as described in greater detail below, the tubular section 202and the flange 204 may rotate together in a rotation direction 109 tomove through the fitting unit 104 and the sensing unit 106 as the tuberollers 102 support and rotate the tubular section 202. For example, theflange 204 may be supported (e.g., hung from an overhead crane or asimilar support) and initially secured (e.g., tack welded) to thetubular section 202 such that the flange 204 and the tubular section 202rotate together in the rotation direction 109. As also described ingreater detail below, the controller 108 may receive an indication of aradial offset 210 detected by the sensing unit 106 and, based on acomparison of the radial offset 210 to a target value, the controllermay actuate the fitting unit 104 to adjust the radial offset 210 betweenthe tubular section 202 and the flange 204. Significantly, it should beappreciated that the adjustment of the radial offset 206 as the tubularsection 202 and the flange 204 rotate in the rotation direction 109, asdescribed herein, may reduce time, alignment error, labor costs, or acombination thereof as compared to manual attachment processes.

Referring now to FIGS. 1, 2A, 2B, 2C, 3A, and 3B, the tubular section202 may be supported by the tube rollers 102. For example, the tuberollers 102 may be positioned along a lower portion 302 of the tubularsection 202 such that the force of gravity acting on the tubular section202 maintains contact between the tubular section 202 and the tuberollers 102. As used herein, the lower portion 302 of the tubularsection 202 shall be understood to be a portion of the tubular section202 generally below a maximum horizontal dimension of the tubularsection 202 supported on the tube rollers 102. For the sake of clarity,as the tubular section 202 rotates in the rotation direction 109, thelower portion 302 shall be understood to be the portion of the tubularsection 202 generally below the maximum horizontal dimension of thetubular section 202 at a corresponding point in time. That is, the lowerportion 302 of the tubular section 202 shall be understood to be definedwith respect to a fixed coordinate system, even as the tubular section202 rotates in the rotation direction 109.

With the lower portion 302 of the tubular section 202 in contact withthe tube rollers 102, at least one instance of the tube rollers 102 maybe actuatable to rotate the tubular section 202 in the rotationdirection 109. In certain implementations, while at least one of thetube rollers 102 is actuatable to rotate the tubular section in therotation direction 109, one or more other instances of the tube rollers102 may be passive. In this context, a passive instance of the tuberollers 102 may be in contact with the tubular section 202 to exert aradial force on the tubular section 202 as the one or more actuatedinstances of the tube rollers 102 exert a radial force on the tubularsection 202 while also exerting a rotational force to move the tubularsection 202 in the rotation direction 109.

The force of gravity acting on the tubular section 202 supported by thetube rollers 102 may cause the tubular section 202 to sag betweeninstances the tube rollers 102. In turn, such sagging of the tubularsection 202 may contribute to a poor shape mismatch between the tubularsection 202 and the flange 204 (FIGS. 2A-2C). Thus, to reduce a shapemismatch that may occur between the tubular section 202 and the flange204, spacing of instances of the tube rollers 102 may be controllable,as described in greater detail below, through actuation prior torotating the tubular section 202 or as the tubular section 202 isrotating in the rotation direction 109. As compared to conventionaltechniques in which passive rollers self-align under the weight of atubular section, controlling the spacing of instances of the tuberollers 102 according to the techniques described herein may change thedistribution of the weight of the tubular section 202 to bring the lowerportion 302 of the tubular section 202 into a shape more closelyapproximating a form with constant radius. Further, or instead, controlover the spacing of instances of the tube rollers 102 may bring thelower portion 302 of the tubular section 202 into a less round shape(e.g., into a shape that more closely approximates a flat line), whichmay be useful for alignment with certain designs of the flange 204.

In general, the term “spacing,” in the context of the plurality of thetube rollers 102, shall be understood to include any of variousdifferent types of orientations in positioning of at least one instanceof the tube rollers 102 relative to another instance of the tube rollers102 and, therefore, relative to the tubular section 202. For example, asdescribed in greater detail below, a change in spacing may include achange in angle of a pair of the tube rollers 102 in contact with thetubular section 202. Additionally, or alternatively, as also describedin greater detail below, a change in spacing may include a change indistance between at least two instances of the tube rollers 102 incontact with the tubular section 202. More generally, unless otherwisespecified or made clear from the context, a change in spacing of atleast one instance of the tube rollers 102 relative to another instanceof the tube rollers 102 shall be understood to be a controlled change inposition of the tube rollers 102 to produce a corresponding change inshape of the lower portion 302 of the tubular section 202.

In certain implementations, the fit-up system 100 may include a firstroller assembly 304 and a second roller assembly 306. The first rollerassembly 304 may include a first set 308 of the tube rollers 102, andthe second roller assembly 306 may include a second set 310 of the tuberollers 102. The first set 308 of the tube rollers 102 and the secondset 310 of the tube rollers 102 may be apart from one another along acircumference of the tubular section 202 as the tubular section 202moves along a path of movement in the rotation direction 109. Ingeneral, unless otherwise specified the first set 308 of the tuberollers 102 may include one or more instances of the tube rollers 102,and the second set 310 of the tube rollers 102 may include one or moreinstances of the tube rollers 102.

The shape of the portion of the tubular section 202 between the firstset 308 and the second set 310 of the tube rollers 102 is a function of,among other things, the flexibility of the tubular section 202 in theradial direction and the orientation of the first set 308 and the secondset 310 of the tube rollers 102 relative to one another and relative toa surface of the tubular section 202. Thus, given that the flexibilityof the tubular section 202 in the radial direction is typically dictatedby the end use of the tube assembly 200 being formed, it should beappreciated that adjusting the orientation of the first set 308 and thesecond set 310 of the tube rollers 102 relative to one another and/orrelative to the surface of the tubular section 202 may be particularlyuseful for matching the shape of at least a portion of the tubularsection 202 to the flange 204 to achieve control over the radial offset210 at a given point along the circumference of the tubular section 202.In general, actuation of the first set 308 of the tube rollers 102 andthe second set 310 of the tube rollers 102 may increase the efficiencyof the fitting unit 104 and the sensing unit 106 by decreasingdifferences in shape between the tubular section 202 and the flange 204.That is, as the tubular section 202 and the flange 204 are more closelymatched, the degree of actuation of the fitting unit 104 (described ingreater detail below) needed to bring the tubular section 202 and theflange 204 to a desired fit-up may be reduced.

To facilitate controlling a poor shape match between the flange 204 anda portion of the tubular section 202 supported between the first set 308and the second set 310 of the tube rollers 102, the first set 308 of thetube rollers 102 and the second set 310 of the tube rollers 102 may bemovable relative to one another in one or more directions. For example,the first set 308 of the tube rollers 102 and the second set 310 of thetube rollers 102 may be positionable (e.g., slidable) in a horizontaldirection relative to one another to increase or decrease a horizontaldistance between the first set 308 and the second set 310 of the tuberollers 102. Additionally, or alternatively, the first set 308 of thetube rollers 102 may include two or more instances of the tube rollers102 such that the first set 308 of the tube rollers 102 is pivotableabout a first pivot 312. Further, or instead, the second set 310 of thetube rollers 102 may include two or more instance of the tube rollers102 such that the second set 310 of the tube rollers 102 is pivotableabout a second pivot 314. Through such pivoting, the respective anglesof the first set 308 and/or the second set 310 of the tube rollers 102may change to produce a corresponding change in shape of the portion ofthe tubular section 202 between the first set 308 and the second set 310of the tube rollers 102. In such implementations including a first set308 and a second set 310 of the tube rollers 102, each of the first set308 and the second set 310 of the tube rollers 102 may be independentlypivotable relative to the other one of the first set 308 and the secondset 310 of the tube rollers 102. In some implementations, however, thepivoting of the first set 308 and the second set 310 of the tube rollers102 may be linked to one another (e.g., to form mirror symmetric angleswith respect to a vertical plane between the first set 308 and thesecond set 310 of the tube rollers 102).

In certain implementations, the first roller assembly 304 may include anactuator 316 and an electric cylinder 318 to adjust one or more of alinear position or an angle of the first set 308 of the tube rollers 102of the first roller assembly 304. In particular, returning to theexample of the first set 308 of the tube rollers 102 as being pivotableabout the first pivot 312, the electric cylinder 318 may be mechanicallycoupled to the actuator 316 and to the first pivot 312. Morespecifically, the electric cylinder 318 may be offset from an axis ofrotation of the first pivot 312. Through actuation of the actuator 316,the length of the electric cylinder 318 may change. Continuing with thisexample, as a result of the offset of the electric cylinder 318 relativeto the first pivot 312, the change in length of the electric cylinder318 may rotate the first set 308 of tube rollers 102 about the firstpivot 312.

In general, the actuator 316 may be, for example, in electricalcommunication with the controller 108 such that the controller 108 maycontrol the position of the first set 308 of the tube rollers 102through one or more electrical actuation signals delivered to theactuator 316. In general, the first roller assembly 304 and the secondroller assembly 306 are identical to one another (allowing for mirrorsymmetry of components) such that the first set 308 and the second set310 of tube rollers 102 are actuatable to move relative to one another.Thus, for the sake of efficient description, the second roller assembly306 is not described separately and should be understood to operate in amanner analogous to the operation of the first roller assembly 304.

In some implementations, the first set 308 and the second set 310 oftube rollers 102 may be actuated only at an initial setup of the fit-upsystem. For example, the first set 308 and the second set 310 of tuberollers 102 may be actuated at the beginning of a process to bring thelower portion 302 of the tubular section 202 to a desired shape (e.g.,substantially round). Continuing with this example, following theinitial setup, the tube rollers 102 may be held in the same position forthe duration of the process of fitting and joining the flange 204 to thetubular section 202 to form the tube assembly 200. Because the first set308 and the second set 310 of tube rollers 102 are actuated only for alimited period of time, it should be appreciated that suchimplementations may be useful for achieving efficient use of energyand/or preserving useful life of components, each of which may beparticularly advantageous for in-field installations.

While the first set 308 and the second set 310 of tube rollers 102 maybe actuated only at an initial setup in some implementations, otherimplementations may include actuating the first set 308 and the secondset 310 of tube rollers 102 continuously (or at least periodically)during the process of fitting and joining the flange 204 to the tubularsection 202 to form the tube assembly 200. For example, as described ingreater detail below, one or more parameters of the shape of the tubeassembly 200 may be provided (e.g., as a signal from the sensing unit106, as a manual input, or a combination thereof) to the controller 108as part of a feedback control in which the controller 108 sends anactuation signal to actuate the actuator 316 of one or both of the firstroller assembly 304 or the second roller assembly 306 as the tubularsection 202 moves in the rotation direction 109. The actuation of thefirst roller assembly 304, the second roller assembly 306, or acombination thereof may move the tube rollers 102 according to any oneor more of the techniques described herein to achieve a target shape ofthe tubular section 202 and, in turn, form the tube assembly 200according to the one or more shape parameters provided to the controller108.

In general, the first set 308 and the second set 310 of the tube rollers102 may be any combination of driven or passive as may be suitable for aparticular implementation. In some instances, therefore, at least one ofthe tube rollers 102 in each of the first set 308 and the second set 310of the tube rollers 102 may be driven such that corresponding rotationof the respective instance of the tube roller 102 acts on the tubularsection 202 to move the tubular section 202 in the rotation direction109. Additionally, or alternatively, at least one of the tube rollers102 in the first set 308 and the second set 310 of the tube rollers 102may be passive such that rotation of the tubular section 202 in therotation direction 109 imparts rotation to the respective instance ofthe tube roller 102. Thus, in some cases, each of the tube rollers 102in the first set 308 and the second set 310 of the tube rollers 102 maybe driven. In other cases, each of the first set 308 and the second set310 of the tube rollers 102 may include a driven instance of the tuberoller 102 and a passive instance of the tube roller 102. Additionally,or alternatively, each of the tube rollers 102 in the first set 308 andthe second set 310 of the tube rollers 102 may be passive. That is,continuing with this example, the fit-up system may include an endroller 110 generally toward an end portion of the tubular section 202opposite the flange 204, and the end roller 110 may be driven while eachof the tube rollers 102 is passive. Such a combination of driving theend roller 110 as each of the tube rollers 102 are passive may beuseful, for example, for decoupling driving the tubular section 202 andpositioning the first set 308 and the second set 310 of the tube rollers102. In turn, this decoupling may be useful for achieving more robustcontrol over the relative positioning of the flange 204 relative to thetubular section 202.

Referring now to FIGS. 1, 2A, 2B, 2C, 3A, 3B, 4A, and 4B, the fittingunit 104 may include a locating roller 402 and a pusher roller 404spaced relative to one another to define therebetween a pinch 406. Theflange 204 may rotate through the pinch 406 in the rotation direction109 as the pinch 406 controls an axial and radial position of the flange204 relative to the tubular section 202 as the tubular section 202 alsorotates in the rotation direction 109. The pinch 406 may be, forexample, between at least two instance of the tube rollers 102 along apath of movement of the tubular section 202 in the rotation direction109. As a more specific example, the pinch 406 may be generally betweenthe first set 308 of the tube rollers 102 and the second set 310 of thetube rollers 102 along the path of movement of the tubular section 202in the rotation direction 109. That is, a portion of the flange 204 maymove through the pinch 306 as a corresponding portion of the tubularsection 202 is supported between the first set 308 and the second set310 of the tube rollers 102. Such positioning of the pinch 406 withrespect to the first set 308 and the second set 310 of the tube rollers102 may facilitate using the fitting unit 104 and the tube rollers 102in coordination with one another to achieve a target value of the radialoffset 210.

In general, the flange 204 moving through the pinch 406 in the rotationdirection 109 is mechanically coupled to the tubular section 202 (e.g.,through tack welding). Accordingly, the flange 204 and the tubularsection 202 rotate in the rotation direction 109 at the same angularvelocity and, more specifically, without relative rotational movementbetween the flange 204 and the tubular section 202. That is, rotation ofthe tubular section 202 by the tube rollers 102 also rotates the flange204. Thus, in certain implementations, at least one of the locatingroller 402 or the pusher roller 404 of the fitting unit 104 may bepassive with respect to movement of the flange 204 in the rotationdirection 109 through the pinch 406.

In certain implementations, the locating roller 402 may define a channel408 engageable with the radial section 205 of the flange 204. With theradial section 205 of the flange 204 disposed in the channel 408, thelocating roller 402 may restrict axial movement of the flange 204 whilepermitting rotation of the flange 204 in the rotation direction 109. Ingeneral, the channel 408 may have an axial dimension that is slightlylarger than an axial dimension of the radial section 205 of the flange204 such that the locating roller 402 may restrict axial movement of theflange 204 with a reduced likelihood of damaging the flange 204 and/orinterfering with rotational movement of the flange 204 and the tubularsection 202 mechanically coupled to the flange 204.

While the radial offset 210 between the tubular section 202 and theflange 204 has been described as being controllable through spacing ofthe tube rollers 102 to achieve a desired shape of the tubular section202 (under the force of gravity) between at least two instances of thetube rollers 102, it should be appreciated that the position of thelocating roller 402 may additionally or alternatively be adjustable tocontrol the radial offset 210 between the tubular section 202 and theflange 204. For example, the fitting unit 104 may include a firstactuator 410 mechanically coupled to the locating roller 402 and thepusher roller 404. Continuing with this example, actuation of the firstactuator 410 may move the pinch 406 in a direction having a radialcomponent (e.g., vertically in FIG. 4) such that a portion of the flange204 between the pinch 406 also undergoes corresponding movement toadjust the radial offset 210 as the flange 204 and the tubular section202 rotate in the rotation direction 109. In certain instances, thefirst actuator 410 may be in electrical communication with thecontroller 108, and the controller 108 is configured to send one or moresignals to actuate the first actuator 410 to move the locating roller402 and the pusher roller 404 defining the pinch 406. The one or moresignals from the controller 108 to actuate the first actuator 410 may bebased on a user input to the controller. Additionally, or alternatively,as described in greater detail below, the one or more signals from thecontroller 108 to actuate the first actuator 410 may be based onfeedback from the sensing unit 106.

In some implementations, the fitting unit 104 may include a secondactuator 412 mechanically coupled to the locating roller 402 and thepusher roller 404 defining the pinch 406. The second actuator 412 may beoriented relative to the first actuator 410 such that movement actuatedby the second actuator 412 is, for example, substantially perpendicularto movement actuated by the first actuator 410. Thus, continuing withthis example, in instances in which the first actuator 410 is actuatableto move the pinch 406 to adjust the radial offset 210, the secondactuator 412 may be actuatable to move the pinch 406 in the axialdirection. As a more specific example, the second actuator 412 may beactuated only initially as part of an initial set-up to set an axialspacing of the flange 204 relative to the tubular section 202 while thefirst actuator 410 may be actuated continuously or at least periodicallyto provide active control of the pinch 406 and, therefore, the radialoffset 210 as the flange 204 rotates through the pinch 406 in therotation direction 109.

While the second actuator 412 may be actuated only initially in certainimplementations, it should be appreciated the second actuator 412 may beactuated according to one or more other actuation approaches. Forexample, the second actuator 412 may be actuated continuously throughoutoperation of the fit-up system 10. That is, in some instances, thetubular section 202 may move in the axial direction (sometimes referredto as “walking”) relative to the tube rollers 102. Such walking movementmay occur, for example, when the tube rollers 102 are misaligned withrespect to one another. Additionally, or alternatively, walking movementmay be particularly likely to occur when the tubular section 202 has atapered shape such that the tube rollers 102 rest unevenly on thetapered shape. In instances in which the tubular section 202 may beprone to walking movement, continuously or substantially continuouslyactuating the second actuator 412 may be useful for moving the flange204 in the axial direction to move with the tubular section 202.Further, or instead, continuous or substantially continuous actuation ofthe second actuator 412 may be useful for adjusting for irregularitiesin an edge of one or more of the tubular section 202 or the flange 204.

In some implementations, the fitting unit 104 may include a thirdactuator 414 mechanically coupled to the pusher roller 404 andactuatable to move the pusher roller 404 relative to the locating roller402. That is, actuation of the third actuator 414 may change a dimensionof the pinch 406. For example, to facilitate initially mounting theflange 204 in the pinch 406, the third actuator 414 may be actuated tomove the pusher roller 404 in a direction away from the locating roller402, thus increasing the size of the pinch 406. With the flange 204positioned in the pinch 406, the third actuator 414 may be actuated tomove the pusher roller 404 in a direction toward the locating roller402, thus decreasing the size of the pinch 406 to a size suitable forrestricting radial and axial movement of the flange 204 as the flange204 moves through the pinch 406 in the rotation direction 109.Continuing still further with this example, upon completion of the tubeassembly 200, the third actuator 414 may again be actuated to move thepusher roller 404 in the direction away from the locating roller 402 toincrease the size of the pinch 406 and, therefore, facilitate removal ofthe tube assembly 200 from the fit-up system 100.

In general, the first actuator 410, the second actuator 412, and thethird actuator 414 may be any one or more of various differentelectrical, hydraulic, pneumatic, and/or mechanical actuators useful forcontrolling linear movement of respective components of the fitting unit104. For example, to facilitate integration with the controller 108, oneor more of the first actuator 410, the second actuator 412, and thethird actuator 414 may be an electric linear actuator. Such an electriclinear actuator, coupled with control by the controller 108, mayfacilitate precise position control, continuous or at least periodicposition control as the flange 204 and the tubular section 202 rotate inthe rotation direction 109. Further or instead, the first actuator 410,the second actuator 412, and the third actuator 414 may be manuallyadjustable (e.g., through the use of a rack and pinion mechanism). Suchmanual adjustment may be useful, for example, for coarse positionadjustments as part of initial set-up of the fit-up system 100.

Referring now to FIGS. 1, 2A, 2B, 2C, 3A, 3B, 4A, 4B, 5A, 5B, and 5C,the sensing unit 106 may include at least one instance of a sensor 502positioned relative to the pinch 406 of the fitting unit 104 to detectthe radial offset 210 of the flange 204 and the tubular section 202moving in the rotation direction 109. For example, the sensor 502 may bepositioned to detect the radial offset 210 corresponding to a point onthe flange 204 after the respective point has passed through the pinch406 of the fitting unit 104. Such positioning of the sensor 502 may beuseful for, among other things, facilitating measurement of the radialoffset 210 as a feedback parameter useful for controlling at least aradial position of the pinch 406 to achieve a target value of the radialoffset 210 as the tubular section 202 and the flange 204 rotate in therotation direction 109. As a more specific example, the sensor 502 maybe positioned to detect the radial offset 210 at a point between thefirst set 308 of the tube rollers 102 and the second set 310 of the tuberollers 102 along the path of movement of the tubular section 202 in therotation direction 109.

In certain implementations, the sensor 502 may be positionable incontact with one or more of the flange 204 or the tubular section 202moving in the rotation direction 109. For example, the sensor 502 mayinclude a first rod 504 and a second rod 506 aligned along an axis andspaced axially apart from one another across a seam 212 at which theflange 204 and the tubular section 202 are in an abutting relationship(e.g., through joining as described below) to one another. The first rod504 may be biased (e.g., spring-biased) in contact with the flange 204as the flange 204 rotates in the rotation direction 109, and the secondrod 506 may be biased (e.g., spring-biased) in contact with the tubularsection 202 as the tubular section 202 rotates in the rotation direction109.

In certain implementations, the sensor 502 may include a position sensor508 positioned relative to the first rod 504 and the second rod 506 todetected a difference in position of the first rod 504 and the secondrod 506 in the radial direction. The position sensor 508 may be any oneor more of various different types of sensors useful for measuringlinear displacement of the first rod 504 and the second rod 506.Accordingly, examples of the position sensor 508 include one or more ofthe following: encoders (e.g., paired as a reader and a code strip),micropulse sensors, linear variable differential transformer sensors,laser line or point sensors, optical sensors, or vision sensors. While asingle instance of the position sensor 508 is shown in FIGS. 5B and 5C,it should be appreciated that this is for the sake of clarity ofillustration and multiple instances of the position sensor 508 may beused in certain instances. For example, the position of the first rod504 and the position of the second rod 506 may be detected by respectiveinstances of the position sensor 508.

With the first rod 504 in contact with the flange 204 and the second rod506 in contact with the tubular section 202, the difference in positionof the first rod 504 and the second rod 506 detected by the positionsensor 508 corresponds to the radial offset 210 between the flange 204and the tubular section 202 at the position of the sensor 502. Giventhat the sensor 502 may detect the radial offset 210 as the flange 204and the tubular section 202 rotate in the rotation direction 109, theradial offset 210 detected by the sensor 502 at the position of thesensor 502 shall be understood to be a time-varying parameter, with thevariation of the radial offset 210 corresponding to differences in theradial offset 210 corresponding to different positions along acircumference of the tube assembly 200 being formed.

In certain implementations, the first rod 504 and the second rod 506 mayeach be formed of a ceramic material at least along the respectiveportions of the first rod 504 and the second rod 506 positionable incontact with the tubular section 202 or the flange 204, as the case maybe. The ceramic material may be useful, for example, for resisting wearthrough consistent contact with rotating surfaces of the tubular section202 and the flange 204. Further, or instead, as described in greaterdetail below, the tubular section 202 and the flange 204 may be joinedto one another through the use of heat, and the ceramic material mayfacilitate measuring the radial offset 210 near a position at which heatis applied to join the tubular section 202 and the flange 204 to oneanother.

In general, it should be appreciated that the rotation of the tubularsection 202 and the flange 204 in the rotation direction 109 mayinterfere with accurately measuring the radial offset 210. For example,as the tubular section 202 and the flange 204 rotate past the sensor502, the position of the sensor 502 relative to the tubular section 202and the flange 204 may change in the axial direction and/or in theradial direction. More specifically, as the tubular section 202 movesaxially relative to the tube rollers 102 (a movement referred to aboveas “walking”) and the position of the flange 204 is adjusted inaccordance with the movement of the tubular section 202, the position ofthe sensor 502 relative to the tubular section 202 and the flange 204may inadvertently vary over time. This movement of the relative positionof the sensor 502 may, in some cases, result in variation in alignmentof the sensor 502 with respect to the seam 212 over time. Because thisvariation is related to the motion of the tubular section 202 and theflange 204 relative to the sensor 502 and is not related to the actualmagnitude of the radial offset 210, it should be appreciated thatinadvertent variation of the overall position of the sensor 502 relativeto the flange 204 (and, thus, the seam 212) may introduce error into themeasurement of the radial offset 210. Thus, to reduce the errorintroduced by inadvertent changes in the overall relative position ofthe sensor 502 as the tubular section 202 and the flange 204 rotate, thesensor 502 may be positionable with two degrees of freedom to facilitatetracking the seam 212 as the tubular section 202 and the flange 204rotate in the rotation direction 109.

As an example, the sensing unit 106 may include a first cylinder 510 anda second cylinder 512. The first cylinder 510 may be movable to push thesensor 502 in the axial direction into contact with the flange 204.Further, or instead, the second cylinder 512 may be movable to push thesensor 502 in a radial direction into contact with the flange 204 andthe tubular section 202. In certain instances, one or more of the firstcylinder 510 and the second cylinder 512 may be actively driven to pushthe sensor 502 in each respective direction. Additionally, oralternatively, one or more of the first cylinder 510 and the secondcylinder 512 may passively move the sensor 502 to track the position ofthe flange 204 at any given point in time. As an example, the firstcylinder 510 may be an air cylinder biasing the sensor 502 in the axialdirection into contact the flange 204. As another nonexclusive example,the second cylinder 512 may be an air cylinder biasing the sensor 502 inthe radial direction into contact with the tubular section 202 and theflange 204.

In certain instances, one or both of the first cylinder 510 and thesecond cylinder 512 may be actuatable to retract the sensing unit 106away from the tubular section 202 and the flange 204. This may beuseful, for example, for reducing the likelihood of damage to thesensing unit 106 and/or to the tube assembly 200 as the tube assembly200 is removed from the fit-up system 100. Further, or instead,retracting the sensing unit 106 may facilitate initially positioning thetubular section 202 and the flange 204 in the fit-up system 100 at thebeginning of a process to form the tube assembly 200.

In some implementations, the fit-up system 100 may further include ajoining unit 112 positioned relative to the pinch 406 defined by thefitting unit 104 such that the joining unit 112 may join a rotatingpoint of the flange 204 to the tubular section 202 following rotation ofthe given point of the flange 204 through the pinch 406. Thus, morespecifically, the joining unit 112 may join the flange 204 to thetubular section 202 at the rotating point after the fitting unit 104 hasadjusted the radial offset 210 of the rotating point. That is, adjustingthe radial offset 210 prior to joining the flange 204 to the tubularsection 202 has readily appreciable advantages with respect to thedegree of adjustment achievable in the radial offset 210 and the forcerequired to achieve such adjustment.

The joining unit 112 may include, for example, a weld head 514 suitablefor joining the tubular section 202 and the flange 204 to one anotherusing any welding technique compatible with the respective materials ofthe tubular section 202 and the flange 204. A variety of weldingtechniques are known in the art and may be adapted for joining thetubular section 202 and the flange 204 to one another as contemplatedherein. This can, for example, include any welding technique that meltsthe flange 204 or other material along the seam 212, optionally alongwith a filler material added to the joint to improve the strength of thebond. Conventional welding techniques suitable for structurally joiningmetal include, by way of example and not limitation: gas metal arcwelding (GMAW), including metal inert gas (MIG) and/or metal active gas(MAG); submerged arc welding (SAW); laser welding; and gas tungsten arcwelding (also known as tungsten, inert gas or “TIG” welding); and manyothers. These and any other techniques suitable for forming a structuralbond between the tubular section 202 and the flange 204 may be adaptedfor use in the weld head 514 as contemplated herein. Mechanical couplingimparted by the weld head 514 may be, for example, continuous along theseam 212 to provide enhanced structural strength to the tube assembly200 being formed.

In some instances, the weld head 514 may complete a full weld in asingle continuous rotation of the tubular section 202 and the flange 204in the rotation direction 109. However, in instances in which materialsof the tubular section 202 and/or the flange 204 are too thick for asingle weld pass to achieve a suitable weld quality, the weld head 514may continuously join the tubular section 202 and the flange 204 with asingle tack pass. Continuing with this example, additional weld passesmay be completed by the weld head 514. Additionally, or alternatively,the tubular section 202 and the flange 204 may be joined to one anotherwith a single tack pass and removed from the fit-up system 100 such thatadditional welding passes may be completed in a separate welding unit.

In general, the sensing unit 106 may be fixed relative to (e.g.,directly mechanically coupled to) the joining unit 112 to detect theradial offset 210 at a fixed location relative to the joining unit 112.In certain instances, the sensing unit 106 may be fixed relative to thejoining unit 112 to detect the radial offset 210 at a point at or afterthe joining unit 112. That is, as the tubular section 202 and the flange204 are being or have been joined to one another at a rotating point andthat rotating point moves through the fixed location of the sensing unit106, the sensing unit 106 may detect the radial offset 210. Detectingthe radial offset 210 at or just after the weld may advantageouslyreduce the likelihood of a change in the radial offset 210 between thepoint at which the radial offset 210 is detected and when the tubularsection 202 and the flange 204 are joined to one another. While thesensing unit 106 may be fixed relative to the joining unit 112 tomeasure the radial offset 210 at or after the joining unit 112 in someinstances, it should be appreciated that the sensing unit 106 mayadditionally or alternatively be fixed relative to the joining unit 112to measure the radial offset 210 at a rotating point of the tubularsection 202 and the flange 204 before that rotating point moves past thejoining unit 112. Such relative positioning may be useful, for example,for facilitating actively adjusting the radial offset 210 at therotating point before the rotating point moves past the joining unit112.

Combining aspects of the foregoing examples, it should be generallyunderstood that a point on the flange 204 rotating in the rotationdirection 109 may pass through the components of the fit-up system inthe following order: through the fitting unit 104 (where the radialoffset 210 corresponding to the rotating point may be adjusted), throughthe joining unit 112 (where the flange 204 may be joined to the tubularsection 202 at the rotating point), and through the sensing unit 106(where the sensor 502 may detect the radial offset 210 at the rotatingpoint). In general, to facilitate accurate control of the radial offset210 according to any one or more of the control techniques describedherein, it should be appreciated that it may be useful to carry outthese operations in proximity to each other. For example, such proximitymay reduce temporal delay in an automated or semi-automated feedbackcontrol loop carried out by the controller 108.

To facilitate detecting the radial offset 210 in close proximity to thejoining unit 112 in instances in which the joining unit 112 includes theweld head 514, the sensing unit 106 may generally include featuresuseful for withstanding the heat and electrical fields associated withproximity to the weld head 514. Thus, as described above, at leastportions of the first rod 504 and the second rod 506 may be formed of aceramic material capable of withstanding contact with high temperaturesurfaces of the tubular section 202 and the flange 204 in the vicinityof the weld head 514 as the weld head 514 welds the tubular section 202and the flange 204 together at the seam 212. As an example, the ceramicmaterial may include one or more of alumina or alumina-silica.

Additionally, or alternatively, the sensor 502 may include a cooler 516in thermal communication with a volume 503 defined by the sensor 502 tocool any one or more components of the sensor 502 at least partiallydisposed in the volume 503 (e.g., a portion of the first rod 504, aportion of the second rod 506, and the position sensor 508). The cooler516 may include a fluid inlet 518 and a fluid outlet 520 each in fluidcommunication with a cooling chamber 522 defined by the cooler 516. Inuse, the cooling fluid may enter the cooler 516 via the fluid inlet 518,move through the cooling chamber 522 to remove heat from the sensor 502,and exit the cooler 516 via the fluid outlet 520. In some instances, thecooler 516 may be in thermal communication with the volume 503 viathermal conduction. For example, the cooler 516 may be adjacent to thevolume 503. As another example, the cooler 516 may at least partiallydefine the volume 503. Additionally, or alternatively, the cooling fluidmay be any one or more of various different fluids having a heatcapacity suitable for providing cooling to the sensor 502. In someinstances, the cooling fluid may provide cooling to the sensor 502without changing phase in the cooler 516. This may be useful for, amongother things, controlling the rate of flow of the cooling fluid throughthe cooler 516. In other implementations, the cooling provided by thecooling fluid to the sensor 502 may include a phase change. Given itsubiquity and ease of handling, water may be a particularly usefulcooling fluid for use in the cooler 516.

In general, the controller 108 may include any processing circuitry toreceive sensor signals and responsively control operation of the fit-upsystem 100. This may, for example, include dedicated circuitry toexecute processing logic as desired or required, or this may include amicrocontroller, a proportional-integral-derivative controller, or anyother programmable process controller. This can also or instead includea general-purpose microprocessor, memory, and related processingcircuitry configured by computer-executable code to perform the variouscontrol steps and operations described herein. More specifically, thecontroller 108 may control the radial offset 210 of the tubular section202 and the flange 204 relative to one another as the tubular section202 and the flange 204 rotate in the rotation direction 109 in acontinuous process for fitting the flange 204 to the tubular section 202to form the tube assembly 200. For the sake of illustration and clarityof explanation, the controller 108 is described herein as being acentral controller. It shall be understood, however, aspects of thecontroller 108 may be spatially distributed without departing from thescope of the present disclosure.

The controller 108 may include a processing unit 114, a storage medium116 (e.g., a non-transitory, computer-readable storage medium), and auser interface 118. The storage medium 116 and the user interface 118may be in electrical communication with the processing unit 114. Thestorage medium 116 may store computer-executable instructions that, whenexecuted by the processing unit 114, cause the fit-up system 100 toperform one or more of the fitting methods described herein. Theprocessing unit 114 may, further or instead, be responsive to inputreceived through the user interface 118 (e.g., a keyboard, a mouse,and/or a graphical user interface) such that the processing unit 114 isresponsive to input received through the user interface 118 as theprocessing unit 114 executes one or more of the fitting methodsdescribed herein.

In certain implementations, the tubular section 202 and the flange 204may be initially joined to one another in a small section (e.g., by atack weld). The radial offset 210 may be set either manually orautomatically. Further, or instead, a slope of the radial offset 210 maybe set for compatibility with continued correct fit-up. Once the smallsection of the flange 204 is joined to the tubular section 202, thetubular section 202 and the flange 204 may be rotated and at least theadjustment of the radial offset 210 may proceed automatically as theprocessing unit 114 carries out one or more computer executableinstructions stored on the storage medium 116

FIG. 6 is a flowchart of an exemplary method 600 of fitting a flange toa tubular section to form a tubular assembly. It should be appreciatedthat the exemplary method 600 may be carried out, for example, by anyone or more of the fit-up systems (e.g., the fit-up system 100 inFIG. 1) described herein to form any one or more of the tubularassemblies (e.g., the tube assembly 200 in FIGS. 1 and 2) describedherein. For example, one or more steps of the exemplary method 600 maybe carried out by a processing unit of a controller (e.g., theprocessing unit 114 of the controller 108 in FIG. 1). Additionally, oralternatively, one or more steps in the exemplary method 600 may becarried out by an operator providing inputs (e.g., through the userinterface 118 of the controller 108 in FIG. 1) to the controller.

As shown in step 610, the exemplary method 600 may include rotating thetubular section in a direction toward a joining unit. In general, thetubular section may be any one or more of the tubular sections describedherein, and the joining unit may be any one or more of the joining unitsdescribed herein. Thus, for example, the tubular section may besupported on a plurality of tube rollers according to any one or more ofthe various different techniques described herein. As a more specificexample, each tube roller in the plurality of tube rollers may be spacedapart from one another circumferentially along an outer surface of thetubular section. By driving one or more of the tube rollers and/or anend roller in contact with the outer surface of the tubular section, thetubular section may rotate in a rotation direction toward the joiningunit, as also described herein.

As shown in step 612, the exemplary method 600 may include rotating atleast one portion of the flange in the direction toward the joiningunit. In general, the at least one portion of the flange should begenerally understood to include at least one portion of any one or moreof the various different types of flanges described herein. Thus, forexample, the at least one portion of the flange may be a circumferentialsection of a segmented flange. In instances in which the flange issegmented, sections of the flange may be supported on a structure thatholds these sections in a circumferential configuration. In certaininstances, each section of the segmented flange may be attached (e.g.,through an initial tack weld) individually to the tubular section aspart of an initial setup. Further, or instead, the at least one portionof the flange may be a unitary flange defining an enclosed,substantially circular shape.

In general, rotating the at least one portion of the flange in thedirection toward the joining unit may include engaging the at least oneportion of the flange according to any one or more of the techniquesdescribed herein (e.g., using the fitting unit 104 of FIG. 1). Thus, forexample, rotating the at least one portion of the flange may includeforming a pinch between two components, with the pinch restrictingmovement of the at least one portion of the flange in the radialdirection and the axial direction as the at least one portion of theflange rotates in the direction toward the joining unit under rotationalforce imparted by the tubular section mechanically coupled to the atleast one portion of the flange. As an example, a locating roller and apusher roller may collectively define a pinch, with first surface of theflange engaged by the pusher roller, and a second surface of the atleast one portion of the flange engaged with the locating rolleraccording to any one or more of the various different techniquesdescribed herein.

The at least one portion of the flange and the tubular section may berotated in the same rotational direction (e.g., clockwise orcounterclockwise) to move these components toward the joining unit. Incertain implementations, rotating the at least one portion of the flangeand the tubular section in the same rotational direction may includemechanically coupling the at least one portion of the flange and thetubular section together initially (e.g., through a tack weld atstart-up). With the at least one portion of the flange and the tubularsection coupled together in this way, the at least one portion of theflange and the tubular section may move together—at the same rotationalspeed and in the same direction—toward the joining unit. Additionally,or alternatively, the rotation of the tubular section and the at leastone portion of the flange in the direction toward the joining unit maybe about an axis perpendicular to a direction of gravity. Thisorientation of rotation of the tubular section and the at least oneportion of the flange may be useful, for example, for working with longtubular sections useful for forming large-scale tubular assemblies. Morespecifically, rotating the tubular section and the at least one portionof the flange about an axis perpendicular to the direction of gravity,the length of the tubular section may be decoupled from the ceilingheight of a manufacturing facility in which the exemplary method 600 iscarried out. To form a given tubular structure, longer lengths of thetubular section require fewer welds which, in turn, may reducemanufacturing time and cost. Additionally, or alternatively, by rotatingthe tubular section and the at least one portion of the flange about anaxis perpendicular to the direction of gravity, components of the fit-upsystem may be conveniently located near the ground, where components ofthe fit-up system may be readily accessed for set-up, operation, and/ormaintenance. Further, or instead, rotating the tubular section and theat least one portion of the flange about an axis perpendicular to thedirection of gravity may position the seam between the tubular sectionand the at least one portion of the flange along a substantiallyhorizontal surface. This orientation may be useful for joining thetubular section and the at least one portion of the flange usingsubmerged arc welding. As compared to certain other types of welding,submerged arc welding may be performed more quickly, thus facilitatingwelding as the tubular section and the at least one portion of theflange move in the rotation direction.

As shown in step 614, the exemplary method 600 may include receiving oneor more signals indicative of a radial offset between the tubularsection and the at least one portion of the flange. Thus, for example,the one or more signals indicative of the radial offset may be receivedfrom the one or more sensors as the tubular section and the at least oneportion of the flange move in the direction toward the joining unit.Additionally, or alternatively, the one or more signals indicative ofthe radial offset may be continuous to provide a correspondinglycontinuous indication of the radial offset as the tubular section andthe at least one portion of the flange rotate past the sensor.Continuing with this example, such a continuous indication of the radialoffset may be useful as a feedback signal to achieve appropriate fit-upof the flange to the tubular section.

In general, the one or more signals may correspond to detection carriedout by any one or more of various different types of sensors (e.g., thesensor 502 in FIG. 5) useful for detecting a parameter that may beindicative of the radial offset. Thus, for example, the one or moresignals indicative of the radial offset may include a radial distancebetween a location on the tubular section and a correspondingcircumferential location on the flange. This radial distance may be, forexample, directly measured through contact with the tubular section andthe at least one section of the flange. As may be appreciated, the oneor more signals indicative of the radial offset may be received fromdifferent sources and combined with one another to arrive at ameasurement or at least an approximation of the radial offset.

While directly measuring the radial offset may be useful in certainimplementations to facilitate accurate control over the radial offset,the one or more signals may be used to determine the radial offsetthrough one or more indirect techniques. For example, in a radialdirection, the at least one portion of the flange may be more rigid thanthe tubular section. Thus, continuing with this example, it may beuseful to assume that the at least one portion of the flange isinflexible such that the radial offset may be estimated (e.g., accordingto a model or a known physical relationship) based on a known radialposition of the at least one portion of the flange and one or moresignals indicative of a shape of the tubular section at a givenposition. Thus, continuing still further with this example, the one ormore signals indicative of the radial offset may include one or more ofthe following: a radius of curvature of the tubular section between twotube rollers of the plurality of tube rollers; a stress level in thetubular section; a distance between two points along a circumference ofthe tubular section; or a distance between a point on the tubularsection and a fixed point external to the tubular section. Further, orinstead, the one or more signals indicative of the radial offset mayinclude one or more of the following: torque required to actuate atleast one tube roller of the plurality of tube rollers; rotational speedof at least one tube roller of the plurality of tube rollers; or aposition (e.g., a radial position) of at least one tube roller of theplurality of tube rollers.

In certain implementations, the one or more signals indicative of theradial offset may include a user input (e.g., via the user interface 118of the controller 108 in FIG. 1). For example, a user may visuallyobserve the radial offset as being beyond a threshold value indicated bymarkings on the tubular section and/or the at least one portion of theflange. Additionally, or alternatively, at slow enough rotationalspeeds, the user input may be indicative of a manual measurementperformed by the user as the tubular section and/or the at least oneportion of the flange rotate in the direction of the joining unit.

As shown in step 616, the exemplary method 600 may include comparing theone or more signals indicative of the radial offset to a target value.In certain implementations, the target value may be based on one or moreuser inputs. For example, the one or more user inputs may be indicativeof an overall dimensional tolerance of the tube assembly being formed.Further, or instead, the one or more user inputs may be indicative ofdimensions of the tubular section and the at least one portion of theflange. As an example, the target value may be based on measurements ofcircumferences of the tubular section and the flange formed from the atleast one portion of the flange (e.g., a segmented flange or a unitaryhoop). For example, in instances in which the tubular section and theflange have the same circumferential measurement, the target value maybe set to 0, at least initially. Additionally, or alternatively, ininstances in which the tubular section and the flange have differentcircumferential measurements such that D_(flange)=D₀ and D_(tube)=D₀+ΔDthen a target value, at least initially, of ΔD/2 may facilitate keepingthe tubular section and the flange aligned as the flange is secured tothe tubular section.

In some implementations, the target value may vary as the at least oneportion of the flange and the tubular section rotate in the directiontoward the joining unit. For example, the target value may varyaccording to a predetermined function (e.g., a slope), a model, or acombination thereof. Additionally, or alternatively, the target valuemay vary over time to account (e.g., as part of a feedback controltechnique) for accumulation in error of the radial offset as the flangeis joined to the tubular section to form the tubular assembly.

As shown in step 618, the exemplary method 600 may include, based atleast in part on the comparison of the one or more signals to the targetvalue, adjusting the radial offset between the at least one portion ofthe flange and the tubular section as the tubular section and the atleast one portion of the flange each rotated in the direction toward thejoining unit. In general, the adjustment of the radial offset may becarried out through actuation of any one or more components describedherein for moving the tubular section and the flange relative to oneanother. Thus, for example, adjusting the radial offset may includemoving at least one tube roller of the plurality of tube rollers in adirection having a radial component relative to the tubular section asthe tubular section and the at least one portion of the flange rotate inthe direction toward the joining unit. Further, or instead, adjustingthe radial offset may include pushing the at least one portion of theflange in a direction having a radial component relative to the tubularsection.

In some instances, pushing the tubular section and the flange in one ormore directions having a radial component may be carried out at separatetimes. That is, as an example, the at least one portion of the flangemay be pushed in a direction having a radial component relative to theat least one portion of the flange as the plurality of rollers remain ina fixed radial position and in a fixed axial position as the at leastone portion of the flange and the tubular section each rotate in thedirection toward the joining unit. Further, or instead, one or more ofthe fixed radial position or the fixed axial position of the at leastone tube roller of the plurality of tube rollers may be adjusted as thetubular section is stationary. Given the relative size of the tubularsection relative to the flange in some large-scale industrialapplications, adjusting the position of the tubular section while thetubular section is stationary may be useful for retaining adequatecontrol over the position of the tubular section. Alternatively, in someimplementations, pushing the tubular section and the flange in one ormore directions having a radial component may be carried outcontemporaneously such that the at least one portion of the flange maybe moved, in a direction having a radial component relative to the atleast one portion of the flange, as the at least one tube roller of theplurality of tube rollers moves in the radial direction of the tubularsection.

As shown in step 620, the exemplary method 600 may include joining theat least one portion of the flange to the tubular section as the tubularsection and the at least one portion of the flange rotate in thedirection toward the joining unit. In general, the at least one portionof the flange and the tubular section may be joined to one anotheraccording to any one or more of the techniques described herein. Thus,for example, joining may include welding (e.g., as described withrespect to the weld head 514 in FIG. 5). Additionally, or alternatively,however, joining the at least one portion of the flange and the tubularsection to one another may include mechanically coupling thesecomponents through the use of an adhesive and/or mechanical fastening(e.g., rivets, crimping, etc.), as may be appropriate for a particularapplication.

While certain implementations have been described, other implementationsare additionally or alternatively possible.

For example, while the target value for the radial offset has beendescribed as being variable according to certain techniques, otherapproaches to temporally varying the target value are additionally oralternatively possible. For example, referring now to FIGS. 1, 6 and 7,the tubular section 202 may include first tick marks 702 along thecircumference of the tubular section 202, and the flange 204 may includesecond tick marks 704 along the circumference of the flange 204. In theideal case, in which the radial offset is identical to the target valuearound the entire circumference of the tube assembly 200, the first tickmarks 702 on the tubular section 202 may each align with correspondinginstances of the second tick marks 704 on the flange 204 around theentire circumference of the tube assembly 200. In practicalimplementations, however, the radial offset may deviate from the targetvalue at certain circumferential points as the tube assembly 200 isbeing formed. As these differences accumulate, one or more instances ofthe first tick marks 702 on the tubular section 202 may becomemisaligned relative to corresponding one or more instances of the secondtick marks 704 on the flange 204. By measuring the misalignment, thetarget value may be adjusted, as the tube assembly 200 is being formed,to account for the previous radial misalignment. Further, or instead, ininstances in which the tubular section 202 and the flange 204 havedifferent circumferences, maintaining alignment of the first tick marks702 to the second tick marks 704 may, in turn, maintain appropriatealignment of the different circumferences. That is, aligning the firsttick marks 702 to the second tick marks 704 may be useful for aligningthe tubular section 202 and the flange 204 without the need to measurethe circumference of each component. This is a significant advantage ininstances in which the tubular section 202 and the flange 204 are large(e.g., in implementations associated with forming tubular structures forwind towers), given the difficulty associated with accurately measuringthe respective circumferences of the tubular section 202 and the flange204 when these components are large.

In certain implementations, an alignment sensor 706 (e.g., a camera) maybe directed toward the seam 212 defined by the tubular section 202 andthe flange 204. In use, the alignment sensor 706 may detect acircumferential spacing 708 (with nonzero values indicative ofmisalignment) between the first tick marks 702 on the tubular section202 relative to the second tick marks 704 on the flange 204. Thealignment sensor 706 may be in electrical communication with thecontroller 108 such that the exemplary method 600 may include adjustingthe target value based on the circumferential spacing. For example, theexemplary method 600 may include receiving an indication of thecircumferential spacing 708, and adjusting the target value for theradial offset based on the circumferential spacing 708. Additional oralternative details and implementations for adjusting alignment ofcomponents of a tubular assembly based on tick marks are provided by wayof non-limiting example in U.S. Patent Application Publication20160375476, entitled Spiral Forming, the entire contents of which arehereby incorporated herein by reference.

While fit-up systems and methods have been described with respect toadjustment of a radial offset between a tubular section and a flange,other parameters may be additionally or alternatively adjusted toachieve appropriate fit-up of these components. For example, referringnow to FIGS. 1, 4A, and 8, the fitting unit 104 may additionally oralternatively include a gap sensor 418. Examples of the gap sensor 418include one or more of a laser line sensor, a mechanical gap sensor, andan optical sensor including a camera.

In use, the gap sensor 418 measures an axial gap 802 between the tubularsection 202 and the flange 204 as the tubular section 202 and the flange204 rotate in the rotation direction 109. For example, the gap sensor418 may be supported on the fit-up system 100 at any position suitablefor measuring the axial gap 802 at any one or more positions along thepath of movement of the tubular section 202 and the flange 204 in therotational direction 109, prior to joining of the tubular section 202and the flange 204 at the one or more positions. Thus, by way of exampleand not limitation, the gap sensor 418 may be positioned to detect theaxial gap 802 at or near the pinch 406. Further, or instead, the gapsensor 418 is shown and described as a single sensor, it should beappreciated that multiple instances of the gap sensor 418 may be used tomeasure the axial gap 802 at various different positions along the pathof movement of the tubular section 202 and the flange 204 in therotational direction 109.

In general, the axial gap 802 may be controlled to accommodate thejoining process. That is, the axial gap 802 may be set to facilitatemechanically coupling the tubular section 202 and the flange 204 to oneanother. For example, the joining unit 112 may form a weld in the axialgap 802. Additionally, or alternatively, the tubular section 202 and theflange 204 may be joined to one another in the axial gap 802 usingbrazing, soldering, glue, mechanical connections, or any combinationthereof.

The controller 108 may, for example, receive an indication of the axialgap 802 based on a signal received from the gap sensor 418 and/or asignal received as a manual input (e.g., at the user interface 118) froman operator. The signal received from the operator may be based on oneor more measurements made by the gap sensor 418, in certainimplementations. Additionally, or alternatively, while manual control byan operator may be carried out based on information from the gap sensor418, it should be appreciated that manual control by the operator may beachieved without information from the gap sensor 418 (e.g., in instancesin which the fit-up system 100 does not include a gap sensor).

Based at least in part on the indication of the axial gap 802, thecontroller 108 may actuate the second actuator 412 of the fitting unit104 to adjust the position of the pinch 406 (e.g., by moving at leastthe locating roller 402) in the axial direction. With the flange 204disposed in the pinch 406, such movement of the pinch 406 moves theflange 204 in the axial direction. As the fitting unit 104 adjusts theposition of the pinch 406 in the axial direction, the tubular section202 may remain substantially fixed in the axial direction such that themovement of the pinch 406 and, thus, the flange 204 in the axialdirection changes the axial gap 802.

Referring now to FIGS. 1 and 6, the controller 108 may adjust the axialgap 802 as part of the exemplary method 600. For example, as shown instep 615, the exemplary method 600 may include adjusting an axial gap.In certain instances, an axial gap may be compared to a target gap and,based on the comparison of the axial gap to the target gap, the at leastone portion of the flange may be moved in an axial direction. Suchmovement of the at least one portion of the flange in the axialdirection may be actuated, for example, as the at least one portion ofthe flange and the tubular section rotate in the direction toward thejoining unit. Additionally, or alternatively, the at least one portionof the flange may be moved in the axial direction while the tubularsection remains fixed in the axial direction (e.g., during an initialset-up).

While fit-up systems and fitting methods have generally been describedherein with respect to certain types of flanges, it should beappreciated that these fit-up systems and fitting methods may be usedwith respect to any one or more of various different types of flanges toform tubular assemblies, unless otherwise specified or made clear fromthe context.

For example, referring now to FIG. 9, a tubular assembly 900 may includea tubular section 902 coupled to a flange 904 at a seam 912. For thesake of clear and efficient description, elements of the tubularassembly 900 should be understood to be analogous to or interchangeablewith elements with corresponding 200-series element numbers (e.g., inFIGS. 2A and 2B) described herein, unless otherwise explicitly madeclear from the context and, therefore, are not described separately fromcounterpart 200-series element numbers, except to note differences oremphasize certain features. Thus, for example, the tubular section 902of the tubular assembly 900 should be understood to be analogous to thetubular section 202 of the tube assembly 200 (FIGS. 2A and 2B). Further,or instead, the tubular assembly 900 may be formed using any one or moreof the fit-up systems and methods described herein, unless otherwisestated or made clear from the context.

The flange 904 may include an inner surface 908 and an outer surface 920opposite the inner surface 908. The flange 904 may include a firstradial section 905 and a second radial section 924. The first radialsection 905 may extend radially away from the inner surface 908, and thesecond radial section 924 may extend radially outward away from theouter surface 920. With the first radial section 905 and the secondradial section 924 disposed opposite one another, the overall shape ofthe flange 904 may be a “T.” In use, a locating unit (e.g., the fittingunit 104 in FIG. 1) may engage one or both of the first radial section905 and the second radial section 924 to control axial positioning ofthe flange 904 relative to the tubular section 902. Further, or instead,the locating unit may control a radial offset between the tubularsection 902 and the flange 904 according to any one or more of thetechniques described herein for controlling the radial offset.

As another example, while the flange 904 may have an axial portion 907(e.g., as indicated by the inner surface 908 and the outer surface 920)suitable for accommodating sensing of a radial position and/or axialposition of the flange 904, it should be appreciated that the axialportion 907 may, in some instances, have small dimensions approachingand including zero. That is, continuing with the example in which theflange 904 does not have an axial portion, first radial section 905 andthe second radial section 924 of the flange 904 may be mounted directlyto the tubular section 902 at the seam 912. Implementations based onthis flange configuration (sometimes referred to as a “flat flange”) mayinclude, for example, detecting a radial offset between the flange 904and the tubular section 902 by detecting a position of a respectivemaximum radial position of one or both of the first radial section 905or the second radial section 924 relative to an inner surface 906 or anouter surface 926.

As still another example, while certain approaches to controllingpositions of tubular sections have been described, other approaches topositional control of tubular sections are additionally or alternativelypossible. For example, referring now to FIGS. 10A and 10B, a fit-upsystem 1000 may include a hold-down unit 1020, which may be particularlyuseful in instances in which the tubular section 202 is lightweight suchthat the force of gravity alone is insufficient to retain the tubularsection 202 in place on tube rollers as a fit-up process is implemented.It should be understood that the fit-up system 1000 is analogous to orinterchangeable with the fit-up system 100, unless otherwise indicatedor made clear from the context. Thus, for the sake of clear andefficient description, the fit-up system 1000 is described with respectto the hold-down unit 1020 and other aspects of the fit-up system 1000having an analog in the fit-up system 100 are not described separately.

In general, at least a portion of the hold-down unit 1020 may include ahold-down roller 1022 and an actuator 1024 in mechanical communicationwith the hold-down roller 1022. The hold-down roller 1022 may be any oneor more of a ball transfer or a cylindrical (flat or crowned) rollersuch that the hold-down roller 1022 may roll along the inner surface ofthe tubular section 202 as the tubular section 202 rotates in therotation direction 1009. In general, the actuator 1024 may impart linearmotion to the hold-down roller 1022. For example, the actuator 1024 mayinclude any one or more of the pneumatic cylinder, a hydraulic cylinder,an electric cylinder, an electric motor and screw, etc.

The actuator 1024 may be in electrical communication with a controller(e.g., the controller 108 in FIG. 1). In use, the actuator 1024 maymaintain the hold-down roller 1022 in contact with the tubular section202 at a position between two sets of tube rollers (e.g., between thefirst set 308 of tube rollers 102 and the second set 310 of tube rollers102 in FIG. 3A). That is, more specifically, the actuator 1024 maymaintain the position of the hold-down roller 1022 in contact with aninner surface of the tubular section 202 while an outer surface of thetubular section 202 is in contact with a first set of tube rollers and asecond set of tube rollers. The resulting force exerted by the hold-downroller 1022 on the inner surface of the tubular section 202 may have acomponent opposite and substantially equal to the collective forceexerted on the tubular section 202 by the fitting unit as part of anyone or more of the fit-up techniques described herein. Through exertionof such force relative to the force exerted by the fitting unit, thehold-down unit 1020 may facilitate controlling inadvertent movement ofthe tubular section 202 in a direction having a radial component.Further, or instead, the hold-down unit 1020 may facilitate controllingthe shape of the tubular section 202 between the two sets of tuberollers.

While pairs of tube rollers have been described as supporting a tubularsection 202, other implementations are additionally or alternativelypossible. For example, a single instance of a tube roller (e.g., thetube roller 102) may be actuated instead of a set of tube rollers. Ascompared to actuating the angle of a set of tube rollers, in instancesin which a single roller is used, the position of the single roller,relative to the tubular section, may be actuated. In certainimplementations, such actuation of a single roller may be used incombination with actuation of one or more sets of tube rollers tofacilitate achieving a high degree of control over the shape of thetubular section.

The above systems, devices, methods, processes, and the like may berealized in hardware, software, or any combination of these suitable forthe control, data acquisition, and data processing described herein.This includes realization in one or more microprocessors,microcontrollers, embedded microcontrollers, programmable digital signalprocessors or other programmable devices or processing circuitry, alongwith internal and/or external memory. This may also, or instead, includeone or more application specific integrated circuits, programmable gatearrays, programmable array logic components, or any other device ordevices that may be configured to process electronic signals. It willfurther be appreciated that a realization of the processes or devicesdescribed above may include computer-executable code created using astructured programming language such as C, an object orientedprogramming language such as C++, or any other high-level or low-levelprogramming language (including assembly languages, hardware descriptionlanguages, and database programming languages and technologies) that maybe stored, compiled or interpreted to run on one of the above devices,as well as heterogeneous combinations of processors, processorarchitectures, or combinations of different hardware and software. Atthe same time, processing may be distributed across devices such as thevarious systems described above, or all of the functionality may beintegrated into a dedicated, standalone device. All such permutationsand combinations are intended to fall within the scope of the presentdisclosure.

Embodiments disclosed herein may include computer program productscomprising computer-executable code or computer-usable code that, whenexecuting on one or more computing devices, performs any and/or all ofthe steps of the control systems described above. The code may be storedin a non-transitory fashion in a computer memory, which may be a memoryfrom which the program executes (such as random access memory associatedwith a processor), or a storage device such as a disk drive, flashmemory or any other optical, electromagnetic, magnetic, infrared orother device or combination of devices. In another aspect, any of thecontrol systems described above may be embodied in any suitabletransmission or propagation medium carrying computer-executable codeand/or any inputs or outputs from same.

The method steps of the implementations described herein are intended toinclude any suitable method of causing such method steps to beperformed, consistent with the patentability of the following claims,unless a different meaning is expressly provided or otherwise clear fromthe context. So, for example performing the step of X includes anysuitable method for causing another party such as a remote user, aremote processing resource (e.g., a server or cloud computer) or amachine to perform the step of X. Similarly, performing steps X, Y and Zmay include any method of directing or controlling any combination ofsuch other individuals or resources to perform steps X, Y and Z toobtain the benefit of such steps. Thus, method steps of theimplementations described herein are intended to include any suitablemethod of causing one or more other parties or entities to perform thesteps, consistent with the patentability of the following claims, unlessa different meaning is expressly provided or otherwise clear from thecontext. Such parties or entities need not be under the direction orcontrol of any other party or entity, and need not be located within aparticular jurisdiction.

It will be appreciated that the methods and systems described above areset forth by way of example and not of limitation. Numerous variations,additions, omissions, and other modifications will be apparent to one ofordinary skill in the art. In addition, the order or presentation ofmethod steps in the description and drawings above is not intended torequire this order of performing the recited steps unless a particularorder is expressly required or otherwise clear from the context. Thus,while particular embodiments have been shown and described, it will beapparent to those skilled in the art that various changes andmodifications in form and details may be made therein without departingfrom the spirit and scope of this disclosure and are intended to form apart of the invention, which is to be interpreted in the broadest senseallowable by law.

What is claimed is:
 1. A system comprising: a plurality of tube rollersupon which a tubular section is supportable as the tubular sectionrotates in a rotation direction, the plurality of tube rollers includinga first set of the tube rollers and a second set of the tube rollers,the first set of the tube rollers and the second set of the tube rollersapart from one another along a circumference of the tubular section asthe tubular section moves along a path of movement in the rotationdirection; a fitting unit including a locating roller and a pusherroller spaced relative to one another to define therebetween a pinchthrough which a flange is rotatable in the rotation direction; a sensingunit including one or more sensors positioned relative to the pinch todetect a radial offset of the flange and the tubular section moving inthe rotation direction the one or more sensors positioned to detect theradial offset of the flange and the tubular section between the firstset of the tube rollers and the second set of the tube rollers along thepath of movement of the tubular section in the rotation direction; and acontroller in communication with the sensing unit and the fitting unit,the controller configured to receive one or more signals indicative ofthe radial offset, to compare the one or more signals indicative of theradial offset to a target value, and, based at least in part on thecomparison, to move the locating roller to adjust the radial offsetbetween the flange and the tubular section moving in the rotationdirection.
 2. The system of claim 1, wherein the first set of the tuberollers and the second set of the tube rollers are actuatable to moverelative to one another.
 3. The system of claim 2, wherein the first setof the tube rollers and the second set of the tube rollers areactuatable to move relative to one another as the tubular section movesin the rotation direction.
 4. The system of claim 1, wherein the pinchdefined by the locating roller and the pusher roller is between at leasttwo of the tube rollers of the plurality of the tube rollers along apath of movement of the tubular section in the rotation direction. 5.The system of claim 1, wherein at least one of the tube rollers of theplurality of the tube rollers is passive.
 6. The system of claim 1, Asystem comprising: a plurality of tube rollers upon which a tubularsection is supportable as the tubular section rotates in a rotationdirection; a fitting unit including a locating roller and a pusherroller spaced relative to one another to define therebetween a pinchthrough which a flange is rotatable in the rotation direction, thefitting unit including an actuator mechanically coupled to the locatingroller and the pusher roller defining the pinch; a sensing unitincluding one or more sensors positioned relative to the pinch to detecta radial offset of the flange and the tubular section moving in therotation direction; and a controller in communication with the sensingunit and the fitting unit, the controller configured to receive one ormore signals indicative of the radial offset, to compare the one or moresignals indicative of the radial offset to a target value, based atleast in part on the comparison, to move the locating roller to adjustthe radial offset between the flange and the tubular section moving inthe rotation direction, and to actuate the first actuator to move thepinch to adjust the radial offset between the flange and the tubularsection moving in the rotation direction.
 7. The system of claim 1,wherein the locating roller defines a channel engageable with the flangeto restrict axial movement of the flange as the flange rotates throughthe pinch in the rotation direction.
 8. A system comprising: a pluralityof tube rollers upon which a tubular section is supportable as thetubular section rotates in a rotation direction; a fitting unitincluding a locating roller and a pusher roller spaced relative to oneanother to define therebetween a pinch through which a flange isrotatable in the rotation direction, the fitting unit including anactuator mechanically coupled to the locating roller, and the actuatoractuatable to change an axial gap between the flange and the tubularsection moving in the rotation direction; a sensing unit including oneor more sensors positioned relative to the pinch to detect a radialoffset of the flange and the tubular section moving in the rotationdirection; and a controller in communication with the sensing unit andthe fitting unit, the controller configured to receive one or moresignals indicative of the radial offset, to compare the one or moresignals indicative of the radial offset to a target value, and, based atleast in part on the comparison, to move the locating roller to adjustthe radial offset between the flange and the tubular section moving inthe rotation direction.
 9. The system of claim 8, wherein at least oneof the locating roller and the pusher roller is passive with respect tomovement of the flange in the rotation direction.
 10. The system ofclaim 1, further comprising a joining unit positioned relative to thepinch to join a point of the flange to the tubular section followingmovement of the point of the flange through the pinch in the rotationdirection.
 11. The system of claim 10, wherein the one or more sensorsare positioned relative to the joining unit to measure the radial offsetat the point of the flange following movement of the point of the flangepast the joining unit.
 12. The system of claim 11, wherein the sensingunit is fixed relative to the joining unit such that the one or moresensors measure the radial offset at a fixed location relative to thejoining unit.
 13. The system of claim 11, further comprising a coolerincluding a fluid inlet, a fluid outlet, and a cooling chamber in fluidcommunication with the fluid inlet and the fluid outlet, wherein thejoining unit includes a welder, the sensing unit defines a volume inwhich at least a portion of each of the one or more sensors is disposed,the volume in thermal communication with the cooling chamber of thecooler.
 14. The system of claim 1, wherein each of the one or moresensors is positionable in contact with one or more of the flange or thetubular section moving in the rotation direction.
 15. The system ofclaim 1, wherein the locating roller is movable in an axial directionrelative to the tubular section engaged by the plurality of tuberollers.
 16. The system of claim 15, further comprising a gap sensorarranged to measure an axial gap between the flange and the tubularsection moving in the rotation direction, wherein the controller isfurther configured to receive a signal indicative of the axial gapbetween the flange and the tubular section moving in the rotationdirection, to compare the axial gap to a target gap, and, based on thecomparison of the axial gap to the target gap, to move the locatingroller in the axial direction relative to the tubular section engaged bythe plurality of tube rollers.
 17. The system of claim 16, wherein thesignal indicative of the axial gap between the flange and the tubularsection includes a user input.
 18. The system of claim 1, wherein theone or more signals indicative of the radial offset include a userinput.